Cytoreductive partial and radical nephrectomies provide equivalent oncologic outcomes in T1–2M1 renal cell carcinoma

BACKGROUND: To compare the effectiveness of cytoreductive partial nephrectomy (CPN) and cytoreductive radical nephrectomy (CRN) in the treatment of metastatic T1–T2 renal cell carcinoma (RCC). METHODS: We obtained the clinical and pathological data of patients with metastatic T1–T2 RCC who underwent CPN or CRN from the Surveillance, Epidemiology, and End Results (SEER) database (https://seer.cancer.gov). Propensity score matching (PSM) was used to balance differences in characteristics between CPN and CRN cases. Kaplan-Meier survival analysis and univariate and multivariate Cox regression were used to assess the effect of partial nephrectomy (PN) versus radical nephrectomy (RN) on overall survival (OS) and cancer-specific survival (CSS). RESULTS: After screening, 866 eligible cases were obtained. During the 1–107 months of follow-up, 500 patients died, 453 (90.6%) of whom died of RCC. The tumor size in the CRN group was significantly greater than that in the CPN group. Kaplan-Meier survival analysis showed that there was no significant difference in OS and CSS between the CPN group and the CRN group before and after matching. Univariate and multivariate Cox regression analysis found that the risk factors for OS were older age at diagnosis [hazard ratio (HR) =1.02, P=0.008], non-clear cell renal cell carcinoma (ccRCC) pathological type (HR =1.69, P=0.002), number of metastases ≥2 (HR =2.13, P<0.001), and regional lymph node involvement (HR =2.22, P=0.004), while the risk factors for CSS were non-ccRCC pathological type (HR =1.51, P=0.021) and the number of metastases ≥2 (HR =2.24, P <0.001). CONCLUSIONS: CPN can provide similar oncologic outcomes as can CRN in T1–2M1 cases, and tumor metastatic burden is a major risk factor for survival in these patients with metastatic renal cell carcinoma (mRCC).